a positive integer n when divided by 9, gives 7 as remainder .What will be the remainder when 3n-1 is divided by 9?

Asked by richaverma914 | 1st Aug, 2015, 07:51: PM

Expert Answer:

begin mathsize 14px style L e t space Q space b e space t h e space q u o t i e n t space b y space n space i s space d i v i d e d space b y space 9. N o w comma space D i v i d e n d space equals space D i v i s o r space cross times space Q u o t i e n t space plus space R e m a i n d e r n equals 9 cross times Q plus 7 n equals 9 Q plus 7  N o w space 3 n minus 1 equals 3 cross times left parenthesis 9 Q plus 7 right parenthesis equals 27 Q plus 21 minus 1 equals 27 Q plus 20 equals 27 Q plus 18 plus 2 W h e n space 3 n minus 1 space i s space d i v i d e d space b y space 9 i. e. space w h e n space 27 Q plus 18 plus 2 space i s space d i v i d e d space b y space 9 i. e. space w h e n space 9 left parenthesis 3 Q plus 2 right parenthesis plus 2 space i s space d i v i d e d space b y space 9 comma space t h e space r e m a i n d e r space i s space 2. end style

Answered by Rashmi Khot | 2nd Aug, 2015, 03:23: PM